Government analysts say solar generation is growing at a faster rate than other fuel sources. (Photo By: Trico)

Solar energy still accounts for just a fraction of U.S. energy use, but it is coming on strong.

Solar power is the fastest-growing source of electric generation in the United States, increasing by 81 percent in 2013 and by 76 percent in 2014, according to the Energy Information Administration.

Small-scale photovoltaics, like rooftop systems, will account for some of the growth. But utility-scale capacity also is projected to more than double between 2012 and 2014, EIA said in its Short-Term Energy Outlook, released Sept. 10.

“EIA expects continued robust growth in the generation of solar energy, although the amount of utility-scale generation remains a small share of total U.S. generation, about 0.3 percent by 2014,” the agency said.

Several electric cooperatives have been adding solar capacity. EIA said it expects additional large solar thermal generation projects to come online in 2013 and 2014 as production costs fall.

Gains in solar also will help to offset some of the loss in renewable hydropower, EIA said.

Mild conditions and lower precipitation levels will cause hydro production to fall by 3.8 percent in 2013, but non-hydro renewable like solar and wind will jump by 7.8 percent in 2013 and 4.1 percent in 2014.

The agency sets a threshold of 1 megawatt for collecting information from utility-scale generation. It’s a challenge, though, to gather reliable data from the thousands of small rooftop commercial and residential solar PV installations, EIA added.

Wind capacity will increase by 3.9 percent in 2013, compared with 2012, and now accounts for about 4 percent of electric generation.